JP 2003-152575A discloses a device which includes a plurality of frequency division multiple receivers and tunes the respective receivers to channels for different broadcasting service areas. The device is thus capable of receiving traffic information of multiple regions.
A receiver is made for wirelessly receiving only traffic information from traffic information broadcasting stations (hereinafter, this receiver is called a traffic information receiver); another receiver is made for wirelessly and selectively receiving the traffic information and radio programs from radio broadcasting stations (hereinafter, this receiver is called a radio receiver). The traffic information broadcasting stations can be located in multiple regions (as prefectures or states); thereby, the traffic information may be received from more than one traffic information broadcasting station at a border between the regions. A system may include both the traffic information receiver and radio receiver. This system may be used in the above border, which may cause the problem below.
A vehicle having the system may come close to the border between a current region and a neighboring region while receiving traffic information of the current region by using one of the receivers included in the system. In this case, this system can further receive traffic information of the neighboring region by using the other receiver. Thus, the system can simultaneously receive traffic information of multiple regions. However, if the radio receiver has been tuned to a radio program by the user and is then suddenly tuned to the traffic information of the neighboring region simply upon approaching the border, the user cannot continue to listen to the radio program. This degrades a merit or user-friendliness in the radio receiver as a radio tuner.